I started out turning pens on a mini lathe with no problem but since then I have gotten a jet 16 42 lathe and I wanted to turn a few pens but I can't seem to get the tool rest close enough to the wood on the mandrel...any comments would help..
Why exactly is it you can't get the tool rest close?
Is the rest longer than your mandrel (so it doesn't fit between headstock and tailstock)?
Or is it because the banjo won't move any closer to the center axis of your lathe? And if it's this, why is that? Maybe the toolrest post is sticking out below the bottom of the banjo, and hitting the side of the ways as you try to move it closer?
If the problem is in your banjo, I don't think getting a shorter toolrest is going to solve it.
Maybe take a photo showing how this is happening.